Get rid of the race conditions by first checking to make sure that a duplicate...

Get rid of the race conditions by first checking to make sure that a duplicate node does not already exist before inserting nodes into the different caches.

Reviewed by: bnicholes, minfrin, jjclar


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@104482 13f79535-47bb-0310-9956-ffa450edef68